gin/v8_platform.cc - chromium/src - Git at Google

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "gin/public/v8_platform.h"

 #include <algorithm>

 #include "base/allocator/partition_allocator/page_allocator.h"
 #include "base/bind.h"
 #include "base/debug/stack_trace.h"
 #include "base/location.h"
 #include "base/sys_info.h"
 #include "base/task_scheduler/post_task.h"
 #include "base/task_scheduler/task_scheduler.h"
 #include "base/trace_event/trace_event.h"
 #include "build/build_config.h"
 #include "gin/per_isolate_data.h"

 namespace gin {

 namespace {

 constexpr base::TaskTraits kBackgroundThreadTaskTraits = {
     base::TaskPriority::USER_VISIBLE};

 base::LazyInstance<V8Platform>::Leaky g_v8_platform = LAZY_INSTANCE_INITIALIZER;

 void RunWithLocker(v8::Isolate* isolate, v8::Task* task) {
   v8::Locker lock(isolate);
   task->Run();
 }

 class IdleTaskWithLocker : public v8::IdleTask {
  public:
   IdleTaskWithLocker(v8::Isolate* isolate, v8::IdleTask* task)
       : isolate_(isolate), task_(task) {}

   ~IdleTaskWithLocker() override = default;

   // v8::IdleTask implementation.
   void Run(double deadline_in_seconds) override {
     v8::Locker lock(isolate_);
     task_->Run(deadline_in_seconds);
   }

  private:
   v8::Isolate* isolate_;
   std::unique_ptr<v8::IdleTask> task_;

   DISALLOW_COPY_AND_ASSIGN(IdleTaskWithLocker);
 };

 void PrintStackTrace() {
   base::debug::StackTrace trace;
   trace.Print();
 }

 class ConvertableToTraceFormatWrapper final
     : public base::trace_event::ConvertableToTraceFormat {
  public:
   explicit ConvertableToTraceFormatWrapper(
       std::unique_ptr<v8::ConvertableToTraceFormat>& inner)
       : inner_(std::move(inner)) {}
   ~ConvertableToTraceFormatWrapper() override = default;
   void AppendAsTraceFormat(std::string* out) const final {
     inner_->AppendAsTraceFormat(out);
   }

  private:
   std::unique_ptr<v8::ConvertableToTraceFormat> inner_;

   DISALLOW_COPY_AND_ASSIGN(ConvertableToTraceFormatWrapper);
 };

 class EnabledStateObserverImpl final
     : public base::trace_event::TraceLog::EnabledStateObserver {
  public:
   EnabledStateObserverImpl() = default;

   void OnTraceLogEnabled() final {
     base::AutoLock lock(mutex_);
     for (auto* o : observers_) {
       o->OnTraceEnabled();
     }
   }

   void OnTraceLogDisabled() final {
     base::AutoLock lock(mutex_);
     for (auto* o : observers_) {
       o->OnTraceDisabled();
     }
   }

   void AddObserver(v8::TracingController::TraceStateObserver* observer) {
     {
       base::AutoLock lock(mutex_);
       DCHECK(!observers_.count(observer));
       if (observers_.empty()) {
         base::trace_event::TraceLog::GetInstance()->AddEnabledStateObserver(
             this);
       }
       observers_.insert(observer);
     }
     // Fire the observer if recording is already in progress.
     if (base::trace_event::TraceLog::GetInstance()->IsEnabled())
       observer->OnTraceEnabled();
   }

   void RemoveObserver(v8::TracingController::TraceStateObserver* observer) {
     base::AutoLock lock(mutex_);
     DCHECK(observers_.count(observer) == 1);
     observers_.erase(observer);
     if (observers_.empty()) {
       base::trace_event::TraceLog::GetInstance()->RemoveEnabledStateObserver(
           this);
     }
   }

  private:
   base::Lock mutex_;
   std::unordered_set<v8::TracingController::TraceStateObserver*> observers_;

   DISALLOW_COPY_AND_ASSIGN(EnabledStateObserverImpl);
 };

 base::LazyInstance<EnabledStateObserverImpl>::Leaky g_trace_state_dispatcher =
     LAZY_INSTANCE_INITIALIZER;

 }  // namespace

 class V8Platform::TracingControllerImpl : public v8::TracingController {
  public:
   TracingControllerImpl() = default;
   ~TracingControllerImpl() override = default;

   // TracingController implementation.
   const uint8_t* GetCategoryGroupEnabled(const char* name) override {
     return TRACE_EVENT_API_GET_CATEGORY_GROUP_ENABLED(name);
   }
   uint64_t AddTraceEvent(
       char phase,
       const uint8_t* category_enabled_flag,
       const char* name,
       const char* scope,
       uint64_t id,
       uint64_t bind_id,
       int32_t num_args,
       const char** arg_names,
       const uint8_t* arg_types,
       const uint64_t* arg_values,
       std::unique_ptr<v8::ConvertableToTraceFormat>* arg_convertables,
       unsigned int flags) override {
     std::unique_ptr<base::trace_event::ConvertableToTraceFormat>
         convertables[2];
     if (num_args > 0 && arg_types[0] == TRACE_VALUE_TYPE_CONVERTABLE) {
       convertables[0].reset(
           new ConvertableToTraceFormatWrapper(arg_convertables[0]));
     }
     if (num_args > 1 && arg_types[1] == TRACE_VALUE_TYPE_CONVERTABLE) {
       convertables[1].reset(
           new ConvertableToTraceFormatWrapper(arg_convertables[1]));
     }
     DCHECK_LE(num_args, 2);
     base::trace_event::TraceEventHandle handle =
         TRACE_EVENT_API_ADD_TRACE_EVENT_WITH_BIND_ID(
             phase, category_enabled_flag, name, scope, id, bind_id, num_args,
             arg_names, arg_types, (const long long unsigned int*)arg_values,
             convertables, flags);
     uint64_t result;
     memcpy(&result, &handle, sizeof(result));
     return result;
   }
   void UpdateTraceEventDuration(const uint8_t* category_enabled_flag,
                                 const char* name,
                                 uint64_t handle) override {
     base::trace_event::TraceEventHandle traceEventHandle;
     memcpy(&traceEventHandle, &handle, sizeof(handle));
     TRACE_EVENT_API_UPDATE_TRACE_EVENT_DURATION(category_enabled_flag, name,
                                                 traceEventHandle);
   }
   void AddTraceStateObserver(TraceStateObserver* observer) override {
     g_trace_state_dispatcher.Get().AddObserver(observer);
   }
   void RemoveTraceStateObserver(TraceStateObserver* observer) override {
     g_trace_state_dispatcher.Get().RemoveObserver(observer);
   }

  private:
   DISALLOW_COPY_AND_ASSIGN(TracingControllerImpl);
 };

 // static
 V8Platform* V8Platform::Get() { return g_v8_platform.Pointer(); }

 V8Platform::V8Platform() : tracing_controller_(new TracingControllerImpl) {}

 V8Platform::~V8Platform() {}

 void V8Platform::OnCriticalMemoryPressure() {
 #if defined(OS_WIN)
   // Some configurations do not use page_allocator. Only 32 bit Windows systems
   // reserve memory currently.
   base::ReleaseReservation();
 #endif
 }

 size_t V8Platform::NumberOfAvailableBackgroundThreads() {
   return std::max(1, base::TaskScheduler::GetInstance()
                          ->GetMaxConcurrentNonBlockedTasksWithTraitsDeprecated(
                              kBackgroundThreadTaskTraits));
 }

 void V8Platform::CallOnBackgroundThread(
     v8::Task* task,
     v8::Platform::ExpectedRuntime expected_runtime) {
   base::PostTaskWithTraits(FROM_HERE, kBackgroundThreadTaskTraits,
                            base::Bind(&v8::Task::Run, base::Owned(task)));
 }

 void V8Platform::CallOnForegroundThread(v8::Isolate* isolate, v8::Task* task) {
   PerIsolateData* data = PerIsolateData::From(isolate);
   if (data->access_mode() == IsolateHolder::kUseLocker) {
     data->task_runner()->PostTask(
         FROM_HERE, base::Bind(RunWithLocker, base::Unretained(isolate),
                               base::Owned(task)));
   } else {
     data->task_runner()->PostTask(
         FROM_HERE, base::Bind(&v8::Task::Run, base::Owned(task)));
   }
 }

 void V8Platform::CallDelayedOnForegroundThread(v8::Isolate* isolate,
                                                v8::Task* task,
                                                double delay_in_seconds) {
   PerIsolateData* data = PerIsolateData::From(isolate);
   if (data->access_mode() == IsolateHolder::kUseLocker) {
     data->task_runner()->PostDelayedTask(
         FROM_HERE,
         base::Bind(RunWithLocker, base::Unretained(isolate), base::Owned(task)),
         base::TimeDelta::FromSecondsD(delay_in_seconds));
   } else {
     data->task_runner()->PostDelayedTask(
         FROM_HERE, base::Bind(&v8::Task::Run, base::Owned(task)),
         base::TimeDelta::FromSecondsD(delay_in_seconds));
   }
 }

 void V8Platform::CallIdleOnForegroundThread(v8::Isolate* isolate,
                                             v8::IdleTask* task) {
   PerIsolateData* data = PerIsolateData::From(isolate);
   DCHECK(data->idle_task_runner());
   if (data->access_mode() == IsolateHolder::kUseLocker) {
     data->idle_task_runner()->PostIdleTask(
         new IdleTaskWithLocker(isolate, task));
   } else {
     data->idle_task_runner()->PostIdleTask(task);
   }
 }

 bool V8Platform::IdleTasksEnabled(v8::Isolate* isolate) {
   return PerIsolateData::From(isolate)->idle_task_runner() != nullptr;
 }

 double V8Platform::MonotonicallyIncreasingTime() {
   return base::TimeTicks::Now().ToInternalValue() /
       static_cast<double>(base::Time::kMicrosecondsPerSecond);
 }

 double V8Platform::CurrentClockTimeMillis() {
   return base::Time::Now().ToJsTime();
 }

 v8::TracingController* V8Platform::GetTracingController() {
   return tracing_controller_.get();
 }

 v8::Platform::StackTracePrinter V8Platform::GetStackTracePrinter() {
   return PrintStackTrace;
 }

 }  // namespace gin
	// Copyright 2014 The Chromium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "gin/public/v8_platform.h"

	#include <algorithm>

	#include "base/allocator/partition_allocator/page_allocator.h"
	#include "base/bind.h"
	#include "base/debug/stack_trace.h"
	#include "base/location.h"
	#include "base/sys_info.h"
	#include "base/task_scheduler/post_task.h"
	#include "base/task_scheduler/task_scheduler.h"
	#include "base/trace_event/trace_event.h"
	#include "build/build_config.h"
	#include "gin/per_isolate_data.h"

	namespace gin {

	namespace {

	constexpr base::TaskTraits kBackgroundThreadTaskTraits = {
	base::TaskPriority::USER_VISIBLE};

	base::LazyInstance<V8Platform>::Leaky g_v8_platform = LAZY_INSTANCE_INITIALIZER;

	void RunWithLocker(v8::Isolate* isolate, v8::Task* task) {
	v8::Locker lock(isolate);
	task->Run();
	}

	class IdleTaskWithLocker : public v8::IdleTask {
	public:
	IdleTaskWithLocker(v8::Isolate* isolate, v8::IdleTask* task)
	: isolate_(isolate), task_(task) {}

	~IdleTaskWithLocker() override = default;

	// v8::IdleTask implementation.
	void Run(double deadline_in_seconds) override {
	v8::Locker lock(isolate_);
	task_->Run(deadline_in_seconds);
	}

	private:
	v8::Isolate* isolate_;
	std::unique_ptr<v8::IdleTask> task_;

	DISALLOW_COPY_AND_ASSIGN(IdleTaskWithLocker);
	};

	void PrintStackTrace() {
	base::debug::StackTrace trace;
	trace.Print();
	}

	class ConvertableToTraceFormatWrapper final
	: public base::trace_event::ConvertableToTraceFormat {
	public:
	explicit ConvertableToTraceFormatWrapper(
	std::unique_ptr<v8::ConvertableToTraceFormat>& inner)
	: inner_(std::move(inner)) {}
	~ConvertableToTraceFormatWrapper() override = default;
	void AppendAsTraceFormat(std::string* out) const final {
	inner_->AppendAsTraceFormat(out);
	}

	private:
	std::unique_ptr<v8::ConvertableToTraceFormat> inner_;

	DISALLOW_COPY_AND_ASSIGN(ConvertableToTraceFormatWrapper);
	};

	class EnabledStateObserverImpl final
	: public base::trace_event::TraceLog::EnabledStateObserver {
	public:
	EnabledStateObserverImpl() = default;

	void OnTraceLogEnabled() final {
	base::AutoLock lock(mutex_);
	for (auto* o : observers_) {
	o->OnTraceEnabled();
	}
	}

	void OnTraceLogDisabled() final {
	base::AutoLock lock(mutex_);
	for (auto* o : observers_) {
	o->OnTraceDisabled();
	}
	}

	void AddObserver(v8::TracingController::TraceStateObserver* observer) {
	{
	base::AutoLock lock(mutex_);
	DCHECK(!observers_.count(observer));
	if (observers_.empty()) {
	base::trace_event::TraceLog::GetInstance()->AddEnabledStateObserver(
	this);
	}
	observers_.insert(observer);
	}
	// Fire the observer if recording is already in progress.
	if (base::trace_event::TraceLog::GetInstance()->IsEnabled())
	observer->OnTraceEnabled();
	}

	void RemoveObserver(v8::TracingController::TraceStateObserver* observer) {
	base::AutoLock lock(mutex_);
	DCHECK(observers_.count(observer) == 1);
	observers_.erase(observer);
	if (observers_.empty()) {
	base::trace_event::TraceLog::GetInstance()->RemoveEnabledStateObserver(
	this);
	}
	}

	private:
	base::Lock mutex_;
	std::unordered_set<v8::TracingController::TraceStateObserver*> observers_;

	DISALLOW_COPY_AND_ASSIGN(EnabledStateObserverImpl);
	};

	base::LazyInstance<EnabledStateObserverImpl>::Leaky g_trace_state_dispatcher =
	LAZY_INSTANCE_INITIALIZER;

	} // namespace

	class V8Platform::TracingControllerImpl : public v8::TracingController {
	public:
	TracingControllerImpl() = default;
	~TracingControllerImpl() override = default;

	// TracingController implementation.
	const uint8_t* GetCategoryGroupEnabled(const char* name) override {
	return TRACE_EVENT_API_GET_CATEGORY_GROUP_ENABLED(name);
	}
	uint64_t AddTraceEvent(
	char phase,
	const uint8_t* category_enabled_flag,
	const char* name,
	const char* scope,
	uint64_t id,
	uint64_t bind_id,
	int32_t num_args,
	const char** arg_names,
	const uint8_t* arg_types,
	const uint64_t* arg_values,
	std::unique_ptr<v8::ConvertableToTraceFormat>* arg_convertables,
	unsigned int flags) override {
	std::unique_ptr<base::trace_event::ConvertableToTraceFormat>
	convertables[2];
	if (num_args > 0 && arg_types[0] == TRACE_VALUE_TYPE_CONVERTABLE) {
	convertables[0].reset(
	new ConvertableToTraceFormatWrapper(arg_convertables[0]));
	}
	if (num_args > 1 && arg_types[1] == TRACE_VALUE_TYPE_CONVERTABLE) {
	convertables[1].reset(
	new ConvertableToTraceFormatWrapper(arg_convertables[1]));
	}
	DCHECK_LE(num_args, 2);
	base::trace_event::TraceEventHandle handle =
	TRACE_EVENT_API_ADD_TRACE_EVENT_WITH_BIND_ID(
	phase, category_enabled_flag, name, scope, id, bind_id, num_args,
	arg_names, arg_types, (const long long unsigned int*)arg_values,
	convertables, flags);
	uint64_t result;
	memcpy(&result, &handle, sizeof(result));
	return result;
	}
	void UpdateTraceEventDuration(const uint8_t* category_enabled_flag,
	const char* name,
	uint64_t handle) override {
	base::trace_event::TraceEventHandle traceEventHandle;
	memcpy(&traceEventHandle, &handle, sizeof(handle));
	TRACE_EVENT_API_UPDATE_TRACE_EVENT_DURATION(category_enabled_flag, name,
	traceEventHandle);
	}
	void AddTraceStateObserver(TraceStateObserver* observer) override {
	g_trace_state_dispatcher.Get().AddObserver(observer);
	}
	void RemoveTraceStateObserver(TraceStateObserver* observer) override {
	g_trace_state_dispatcher.Get().RemoveObserver(observer);
	}

	private:
	DISALLOW_COPY_AND_ASSIGN(TracingControllerImpl);
	};

	// static
	V8Platform* V8Platform::Get() { return g_v8_platform.Pointer(); }

	V8Platform::V8Platform() : tracing_controller_(new TracingControllerImpl) {}

	V8Platform::~V8Platform() {}

	void V8Platform::OnCriticalMemoryPressure() {
	#if defined(OS_WIN)
	// Some configurations do not use page_allocator. Only 32 bit Windows systems
	// reserve memory currently.
	base::ReleaseReservation();
	#endif
	}

	size_t V8Platform::NumberOfAvailableBackgroundThreads() {
	return std::max(1, base::TaskScheduler::GetInstance()
	->GetMaxConcurrentNonBlockedTasksWithTraitsDeprecated(
	kBackgroundThreadTaskTraits));
	}

	void V8Platform::CallOnBackgroundThread(
	v8::Task* task,
	v8::Platform::ExpectedRuntime expected_runtime) {
	base::PostTaskWithTraits(FROM_HERE, kBackgroundThreadTaskTraits,
	base::Bind(&v8::Task::Run, base::Owned(task)));
	}

	void V8Platform::CallOnForegroundThread(v8::Isolate* isolate, v8::Task* task) {
	PerIsolateData* data = PerIsolateData::From(isolate);
	if (data->access_mode() == IsolateHolder::kUseLocker) {
	data->task_runner()->PostTask(
	FROM_HERE, base::Bind(RunWithLocker, base::Unretained(isolate),
	base::Owned(task)));
	} else {
	data->task_runner()->PostTask(
	FROM_HERE, base::Bind(&v8::Task::Run, base::Owned(task)));
	}
	}

	void V8Platform::CallDelayedOnForegroundThread(v8::Isolate* isolate,
	v8::Task* task,
	double delay_in_seconds) {
	PerIsolateData* data = PerIsolateData::From(isolate);
	if (data->access_mode() == IsolateHolder::kUseLocker) {
	data->task_runner()->PostDelayedTask(
	FROM_HERE,
	base::Bind(RunWithLocker, base::Unretained(isolate), base::Owned(task)),
	base::TimeDelta::FromSecondsD(delay_in_seconds));
	} else {
	data->task_runner()->PostDelayedTask(
	FROM_HERE, base::Bind(&v8::Task::Run, base::Owned(task)),
	base::TimeDelta::FromSecondsD(delay_in_seconds));
	}
	}

	void V8Platform::CallIdleOnForegroundThread(v8::Isolate* isolate,
	v8::IdleTask* task) {
	PerIsolateData* data = PerIsolateData::From(isolate);
	DCHECK(data->idle_task_runner());
	if (data->access_mode() == IsolateHolder::kUseLocker) {
	data->idle_task_runner()->PostIdleTask(
	new IdleTaskWithLocker(isolate, task));
	} else {
	data->idle_task_runner()->PostIdleTask(task);
	}
	}

	bool V8Platform::IdleTasksEnabled(v8::Isolate* isolate) {
	return PerIsolateData::From(isolate)->idle_task_runner() != nullptr;
	}

	double V8Platform::MonotonicallyIncreasingTime() {
	return base::TimeTicks::Now().ToInternalValue() /
	static_cast<double>(base::Time::kMicrosecondsPerSecond);
	}

	double V8Platform::CurrentClockTimeMillis() {
	return base::Time::Now().ToJsTime();
	}

	v8::TracingController* V8Platform::GetTracingController() {
	return tracing_controller_.get();
	}

	v8::Platform::StackTracePrinter V8Platform::GetStackTracePrinter() {
	return PrintStackTrace;
	}

	} // namespace gin